反应详情

温度

60 °C

To a suspension of (S)-2-tert-butoxycarbonylamino-3-(2,6-dimethyl-4-trifluoromethanesulfonylphenyl)-propionic acid methyl ester (9.68 g, 21.3 mmol), K2CO3 (14.1 g, 0.102 mol), Pd(OAc)2 (0.48 g, 2.13 mmol) and 1,1′-bis(diphenylphosphino)ferrocene (2.56 g, 4.47 mmol) in DMF (48 mL) was bubbled in gaseous CO for 15 min. The mixture was heated to 60° C. for 8 h with a CO balloon. The cool mixture was partitioned between NaHCO3 and EtOAc, and filtered. The aqueous layer was separated, acidified with 10% citric acid aqueous solution, extracted with EtOAc, and finally dried over Na2SO4. Filtration and concentration of the filtrate resulted in a residue. The residue was recrystallized from EtOAc-hexanes to afford the desired product (7.05 g, 94%); 1H NMR (300 MHz, CDCl3): δ 1.36 (9H, s), 2.42 (6H, s), 3.14 (2H, J=7.4 Hz), 3.65 (3H, s), 4.57-4.59 (1H, m), 5.14 (1H, d, J=8.6 Hz), 7.75 (2H, s); MS (ES+) (relative intensity): 251.9 (100) (M−Boc)+.

1. customwas bubbled in gaseous CO for 15 min
2. customThe cool mixture was partitioned between NaHCO3 and EtOAc
3. filtrationfiltered
4. customThe aqueous layer was separated
5. extractionextracted with EtOAc
6. dry with materialfinally dried over Na2SO4
7. filtrationFiltration and concentration of the filtrate
8. customresulted in a residue
9. customThe residue was recrystallized from EtOAc-hexanes